Study on Mature Index of Composting Swine Manure

Two medium -scale composting experiments were carried out to study the e ffects of bulking agents,carbon -to-nitrogen ratio(C /N),aeration forms and additions on swi ne manure composting under moisture content of 68.8%.The changes of various indexes were also evaluated.The maturity evaluation indexes and standards of swine manure composting were put forward.The results obtained were as follows:The solid -state C /N ratio,NH 4+ -N content and the rate of seed germin ation were available to evaluate maturity of swine manure composting.The swine manure composting mature d when solid -state C /N ratio had decreased 20∶1,NH 4+ -N content was 20mg ·kg -1 ,and the rate of seed germination was70%.In this study all treatments could reach their maturity and stabilization in 30to 35days except the treatment with rice hull and the swine manure alone treatment.